Preparation of polyurethanes



United States Patent 3,036,042. PREPARATION OF POLYURETHANES Karl-Ludwig Schmidt, Erwin Miiller, Otto Bayer, and

Kurt Genski, Leverkusen, and Julius Peter, Odenthal,

Germany, assignors, by direct and mesne assignments,

of one-half to Farbenfabriken Bayer Aktiengesellschait,

Leverkusen, Germany, acorporation of Germany, and

one-half to Mobay Chemical Company, Pittsburgh, Pin,

a corporation of Delaware No Drawing. Filed Apr. 3, 1958, Ser. No. 726,024

Claims priority, application Germany Apr. Q, 1957 4 Claims. (Cl. 260-45) This invention relates generally to rubber-like plastics and more particularly to an improved method for making substantially nonporous, rubber-like polyurethanes.

It has been proposed heretofore to prepare a substantially nonporous, rubber-like polyurethane by reacting a saturated linear polyester having terminal hydroxyl groups with an organic diisocyanate and thereafter reacting the resulting intermediate having terminal NCO groups with a suitable cross-linking agent, such as a diamine or a polyhydroxy compound. In one form of this process, the linear polyester is mixed with an excess of organic diisocyanate over that required to react with all of the hydroxyl groups of the polyester and the resulting intermediate having terminal NCO groups is reacted with at least enough unsaturated compound having terminal hydroxyl compounds to react with all terminal NCO groups. In a variation of this process, an unsaturated polyhydroxy compound is used instead of a saturated polyester. As in the other embodiments, an excess of organic diisocyanate is used and sutlicient dihydroxy compound is used as a cross-linker to react with all of the terminal NCO groups of the intermediate compound. In still another variation of the process, an unsaturated diisocyanate is used.

The product obtained from each of the foregoing processes is a horn-like or elastic product which is soluble in most organic solvents and can be cross-linked to form an insoluble product by polymerization with a vinyl compound or with sulfur. It has been also proposed to prepare a millable gum by reacting a polyhydroxy compound such as a polyester with an excess of organic diisocyanate to prepare a prepolymer which is then reacted with a cross-linking agent, such as a glycol much like the process described above. This product is then placed on a rubber mill and the terminal hydroxyl groups of the prepolymer is reacted with additional diisocyanate to form a rubber-like insoluble cross-linked product. This process has the disadvantage of exposing personnel to isocyanates and the product has a tendency to become hot as it is fiexed which deleteriou'sly effects the physical properties of the product.

It is therefore an object of this invention to provide a method for making an improved polyurethane. Another object of the invention is to provide an improved method for making polyurethanes suitable for making rubber-like articles, such as vehicle tires and the like' A further object of the invention is to provide an improved process for making a cross-linked, rubber-like, substantially nonporous polyurethane.

In accordance with this invention, generally speaking, the foregoing objects and others are accomplished by reacting an organic compound having at least twohydrogen atoms, a molecular weight of at least about 1,000 and an hydroxyl number of not more than about 112 with an excess of an organic polyisocyanatc over that required to react with all of the reactive hydrogen atoms and With a dihydroxy cross-linking agent in an amount at least sufiicient to react with all the NCO groups of the reaction product obtained from the organic compound having reactive hydrogen atoms and the organic polyisocyanate.

The resulting millable gum is then Worked on a suitable mill, such as a rubber-roller with an organic peroxide until a cross-linked insoluble product is obtained. The mill-able gum may be prepared by any conventional method, such as, for example, by the process described in German Patent 955,995. The product is then placed on a mill and processed with the organic peroxide.

Any suitable organic compound having at least two hydrogen atoms which will react with an NCO group to form urethane linkages may be used. Examples of such compounds include polyesters prepared by esterification of a dicarboxylic acid and a glycol, polyalkylene ethers having terminal hydroxyl groups, such as the polyethers prepared by condensation of an alkylene oxide or the polymers of tetrahydrofuran having terminal hydroxyl groups, polythioethers having terminal hydroxyl groups prepared by condensation of a thioglycol, such as dithioglycol, polyacetals such as prepared by reaction of formaldehyde with a glycol, and the like. These compounds, however, must have a molecular Weight of at least about 1,000.

Any suitable organic polyisocyanate such as for example, 2,4-toluylene diisocyanate, 2,6-toluylene diisocyanate, 4,4'-diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthylene diisocyanate, m-phenylene-diisocyanate, diphenyl-4,4-diisocyanate, azobenzene-4,4-diisocyanate, diphenylsulphone-4,4-diisocyanate, bis-(3-isocyanatobenzoic acid)-diethylene glycol ester, l-isop'ropylbenzene-3,5-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, tetrame'thylene diisocyanate, and hexamethylene diisocyanate and the like may be used.

The compound used as a cross-linking agent or chain extender may be either a saturated dihydroxy compound or an unsaturated dihydroxy compound. Any suitable compound of this type including 1,4-butenediol, butenedihydroxye'thyl glycol, butynediol, butynedihydroxyethyl glycol, dihydromuconic acid, maleic acid, fumaric acid, esters which contain hydroxyl groups, such as dihydroxyethyl maleate, beta-dihydroxyethyl dihydromuconate and dihydroxyethyl fumara-te, polyesters which are of low molecular weight and contain hydroxyl groups, beta-hydroxyethyl amides of fumaric acid or dihydromuconic acid and the like may be utilized. Other suitable crosslinking agents include 1,3-butanediol, 1,4-butanediol, hydroquinone-beta-diethyl ether, quinl'tol, 4,4'-dihydroxy-dicyclohexyl-dimethyl methane, 4,4-dihydroxy dicyclohexyl methane, 3,3'-dichloro-4,4'-diamino-diphenyl methane, 3,3 dichloro benzidine and N,N dirnethyl-4,4-diaminodiphenyl methane.

Any suitable organic peroxide may be used in the crosslinking step including for example, dicurnyl peroxide, benzoyl peroxide, cyclohexanone hydroperoxide, methylethylketone peroxide, cumene hydroperoxide, diacetyl peroxide, succinyl peroxide, and the like. Dicumyl peroxide has been found to be particularly advantageous and is preferred.

It has been found that best results are obtained when from "about 1 percent to about 10 percent by weight organic peroxide is used. The peroxide may be used as a paste or powder and the paste may be prepared by mixing the peroxide with any of the conventional compounding agents used heretofore, such as for example, calcium carbonate, dibutyl phthalate or the like.

The organic peroxides may be incorporated at room temperature on mixing devices, for example, rubber mixing rollers or worm presses, into the isocyanate-modified condensation and/or polymerization products, and fillers (for example carbon black), or lubricants (for example stearic acid), can be incorporated simultaneously. The cross-linking reaction is then carried out at elevated temperatures, preferably between and C., preferably by pressing and with simultaneous shaping. Times of from about minutes up to about 1 hour are generally suitable.

By comparison with the initially described cross-linking of known type with vinyl compounds, the process of the invention yields plastics of high molecular weight with better mechanical properties, the substantially higher de gree of elasticity being particularly worthy of attention.

Example I About 100 parts by weight of an adipic acid-ethylene glycol polyester with an 01-1 number of about 56 are dehydrated for about 30 minutes at about 135 C. in vacuo in a stirrer-type vessel. About 13.6 parts of p-phenylene diisocyanate are added and allowed to react for about 10 minutes at about 125 C. About 3.5 pants by weight of butenediol are then incorporated by stirring and the mixture quickly becomes viscous. It is poured on to sheet metal plates and heated for about 24 hours at about 110 C. A' rubber-like initial condensate which is soluble in acetone and which has a Defo hardness of about 50/ 80 C., is obtained. 7

About 100 parts by weight of this initial condensate are thoroughly mixed on a rubber roller with about 0.5 part by weight of stearic acid and about 2 parts by weight of dicumyl peroxide and drawn out as a smooth sheet. This is vulcanized for about 120 minutes at about 150 C. in a press. chanical values is obtained:

Tensile strength kg./cm. 213

Breaking elongation percent 670 Rebound elasticity do 42 Shore hardness 44 Permanent elongation percent 6 Example 2 About 100 parts of a polyester obtained from adipic acid and ethylene glycol and 1,2propylene glycol in the ratio of 70:30, the said polyester having a hydroxyl number of 50, are dehydrated in vacuo in a stirrer-type vessel at about 135 C. for 30 minutes. About parts by weight of the addition product of 1 mol of butenediol and 2 mols of 2,4-toluylene diis'ocyanate are thereafter added at 90 C. and the mixture stirred for another 50 minutes at this temperature. The mixture is then poured on to sheet metal plates and heated for about 10 hours at 100 C.

About 100 parts by weight of this. initial condensate are thoroughly mixed on a rubber roller with about parts by weight of active carbon black, about 1 part by weight of stearic acid and about 2 parts by weight of dicumyl peroxide and rolled out to form asheet. This is vulcanized in a press for about 30 minutes at 151 C. The vulcanizate obtained has the following mechanical properties: 4

Tensile strength "kg/cm?" 220 Breaking elongation percent 300 Rebound elasticity .do 32 Shore hardness 60 Permanent elongation percent 6 Example 3 In another embodiment, about 100 parts by weight of the condensate of Example 2 are thoroughly mixed on a A vulcanization with the following me rubber roller with about 30 parts by weight of silicic acid aerogel, about 1 part by weight of stearic acid and about 1.5 parts by weight of tertiary butyl perbenzoate and rolled out to form a sheet. This is vulcanized in a press for 20 minutes at 150 C. The vulcanizate obtained has the following mechanical properties:

Tensile strength kg./cm. 170

Breaking elongation percent 470 Rebound elasticity do 27 Shore hardness- 62 Permanent elongation percent 8 Ring structure kg, abs/4 mm.-- 12 Example 4 Tensile strength kg./cm. 130

Breaking elongation percent 450 Rebound elasticity do 27 Shore hardness- 65 Permanent elongation percent 12 Ring structure kg. abs/4 mm. 10

Example 5 About parts by weight of polybutylene glycol with a hydroxyl number of 40 are dehydrated in vacuo for 30 minutes at 135 C. in a stirrer-type vessel. About 9.3 parts by weight of toluylene diisocyanate are added thereto at C. and reaction is allowed to take place for 30 minutes at 130 to C. About 100 parts by weight of a dihydromuconic acid ethylene glycol ester with a. hydroxyl number of 172 are then incorporated by stirring, allowed to react for 8 minutes, by which time the mixture has become fairly viscous, then poured on to sheet metal plates and heated for 12 hours at 100 C.

About 100 parts by weight of the initial condensate obtained in this manner are mixed on a rubber roller with about 30 parts by weight of active carbon black, about 1 part by weight of stearic acid and about 2 parts by weight of dicumyl peroxide and drawn out as a sheet. Similar results are obtained when 1.5 parts by weight of tertiary butyl perbenzoate or 2 parts by weight of 2,2-bis-(tertiary butyl peroxy)-butane are employed instead of dicumyl peroxide. This sheet is vulcanized for 30 minutes at 151 C. in a press. The vulcanizate obtained has the following mechanical values:

About 900 parts by weight of a polyester prepared by thermal condensation from adipic acid and ethylene glycol and 1,2-propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 5 6 are dehydrated in vacuo in a stirrertype vessel at 130 C. for one hour. About 18 parts by weight of butenediol are admixed with the polyester and when the temperature rises to 100 C. about 114 parts by weight of toluylene diisocyanate are added to the reaction mixture. During the addition of the diisocyanate the temperature rises to about C. After stirring for l to 2 minutes the mixture is poured onto sheet metal plates and heated for 12 hours at 100 C. A thermoplastic material is obtained which can easily be. processed on a rubber mill.

Tensile strength kg./cm. 278

Breaking elongation percent 430 Rebound elasticity do 44 Shore hardness 60 Permanent elongation percent Ring structure kg.abs./4 mm..- 12

Example 7 About 900 parts by weight of a polyester prepared y thermal condensation from adipic acid and ethylene glycol and 1,2-propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 5 6 are dehydrated in vacuo in a stirrertype vessel at 130 C. for one hour. About 164 parts by weight of 4,4-diphenyl methane diisocyanate are admixed with the polyester at this temperature which then rises to about 150 C. After 3 minutes about 18 parts by Weight of butenediol are added. The reaction mixture is stirred for another 2 minutes and then poured onto sheet metal plate and heated for 12 hours at 100 C. A thermoplastic material is obtained having a Defo-hardness of 1900/ 80 and a Defo-elasticity of 33/ 80.

About 100 parts by weight of this intermediate are thoroughly mixed on a rubber mill' with about 30 parts by weight of active carbon black and about 4 parts by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. This is vulcanized in a press for 30 minutes at 150 C. The vulcanizate obtained has the following properties:

About 900 parts by weight of a polyester prepared by thermal condensation from adipic acid and ethylene glycol and 1,2-propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 56 are dehydrated in vacuo in a stirrer-type vessel at 130 C. for one hour. About 18 parts by weight of butene diol are admixed with the polyester and after thoroughly stirring about 113 parts by weight of hexamethylene diisocyanate are added to the reaction mixture. During this operation temperature rises to 140 C. After 5 minutes the mixture is poured onto sheet metal plates and heated for 12 hours at 100 C. A thermoplastic material is thus obtained which can easily be processed on a rubber mill.

About 100 parts of this intermediate are thoroughly mixed on a rubber mill with about 30 parts by weight of active carbon black, about 1 part by weight of stearic acid and about 4 parts by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. This is vulcanized in a press for 30 minutes at 150 C. The vulcanizate obtained has the following mechanical properties:

Tensile strength kg./cm. 270 Breaking elongation percent 420 Rebound'elasticity"; do 46 Shore hardness 74 Permanent elongation; percent 5 Ring structure kg. abs/4 mm 13 6 Example 9 About 300 parts by Weight of a polyester prepared by thermal condensation of adipic acid, ethylene glycol and 1,2 propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 52 are dehydrated in vacuo in a stirrer-type vessel at 130 C. for half an hour. About 32 parts by weight of toluylene diisocyanate are admixed with the polyester. The temperature rises during this operation to 148 C. After 10 minutes 15 parts by weight of a fumaric acid glycol ester having an 0H number of 360 are added. The mixture is stirred for another 3 minutes and then poured onto sheet metal plates and heated for 12 hours at 100 C. A thermoplastic material is thus obtained having a Defo-hardness of 280/80 C. and a Defo-elastieity of 37/ 80 C.

About 100 parts by weight of this intermediate are thoroughly mixed on a rubber mill with about 30 parts by weight of active carbon black and about 4 parts by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. Instead of 4 parts by weight of powdered dicumyl peroxide it is possible to employ about 1.5 parts by weight of ditertiary butyl peroxide. This is vulcanized in a press for 30 minutes at 150 C. The

' vulcanizate obtained has the following mechanical properties:

Tensile strength kg./cm. 233 Breaking elongation percent 340 Rebound elasticity do 41 Shore hardness 61 Permanent elongation percent 4 Ring structure kg. abs/4 mm 11 Example 10 About 900 parts by weight of a polyester prepared by thermal condensation from adipic acid and ethylene glycol and 1,2-propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 5 6 are dehydrated in vacuo in a stirrertype vessel at 130 C. for one hour. About 45 parts by weight of a fumaric acid glycol ester having an OH number of 360 and then about 146 pants by weight of 4,4- diphenyl methane diisocyanate are added, the temperature rising during this operation to about 150 C. After stirring for another 3 minutes the reaotion mixture is poured onto sheet metal plates and heated for 12 hours at 100 C. A thermoplastic material is then obtained having a Defo-hardness of 1350/ C. and a Defo-elastioity of 44/ 80 C.

About parts by weight of this intermediate are thoroughly mixed on a rubber mill with about 30 parts by weight of active carbon black, about 1 part by weight of stearic acid and about 4 parts by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. This is vulcanized in a press for 30 minutes at 150 C. The vulcanizate obtained has the following mechanical properties:

Tensile strength kg./cm. 240

Breaking elongation percent 330 Rebound elasticity do 35 Shore hardness 61 Permanent elongation percent 5 Ring structure kg. abs/ 4 mm 11 Example 11 About 900 parts by weight of a polyester prepared by thermal condensation from adipic acid and ethylene glycol and 1,2-propylene glycol (the glycols being employed in the ratio of 70:30), the said polyester having a hydroxyl number of 56 are dehydrated in vacuo in a stirrertype vessel at C. for one hour. About 45 parts by weight of a bicycloheptene dicarboxylic acid glycol ester havingan OH number of 360 and then about 94 parts by weight of hexamethylene diisocyanate are added, the tem- 7 perature rising during this operation to about 140 to 145 C. After stirring for another minutes the mixture is poured onto sheet metal plates and heated for 12 hours at 100 C. The thermoplastic material thus obtained has a Defo-hardness of 180/ 80 C. and a Defo-elasticity of 35/ 80 C.

About 100 parts of this intermediate are thoroughly mixed on a rubber mill with about 30 parts by weight of active carbon black, about 1 part by weight of stearic acid and about 4 parts by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. Instead of active carbon black about 25 parts by weight of silicic acid aerogel can be employed. This is vulcanized in a press for 30 minutes at 150C. The vulcanizate obtained has the following mechanical properties:

Tensile strength kg/cm?" 170 Breaking elongation percent 220 Rebound elasticity do 40 Shore hardness 85' Permanent elongation percent 5 Ring structure kg. abs/4 mm 12 Example 12 About 1000 parts by weight of polybutylene glycol (OH number 43) are dehydrated in vacuo in a stirrer-type vessel at 130 C. for one hour. About 200 parts by weight of the addition product of 1 mol of butene diol and 2 mols of 2,4-toluylene diisocyanate are thereafter added and the mixture stirred for another minutes. The mixture is then poured onto sheet metal plates and heated for 24 hours at 100 C. The thermoplastic material thus obtained has a Defo-hardness of 375/ 80 C. and a Defoelasticity of 22/ 80 C.

About 100 parts by weight of this intermediate are thoroughly mixed on a rubbermill with about 30 parts by weight of active carbon black and about 4 pants by weight of powdered dicumyl peroxide (40%) and rolled out to form a sheet. This is vulcanized in a press for 30 min-' utes at 150 C. The vulcanizate obtained has the following mechanical properties:

Tensile strength kg./cm. 180

Breaking elongation percent 315 Rebound elasticity do '59 Shore hardness 67 Permanent elongation "percent" 2 Ring structure kg.abs./4 mm 8 Example 13 About 1,000 parts by weight of an adipic acid-ethylene glycol polyester having an hydroxyl number of 56 are dehydrated for one hour at 130 C. in an agitated vessel under vacuum from a water jet. Following this, about pants by weight 1,4-butanediol are added and, as soon as they are well mixed in, about 181 parts by weight 4,4-diphenyl methane-diisocyanaxte are added. Thereupon the temperature will climb to approximately 150 C. Agitation is continued for another 3 minutes, and then the mass is poured into trays and heated in a drying oven for about 12 hours at 100 C. The result is a thermoplastic material with a Defo hardness of 1500/ 80 and a Defo elasticity of 29/ 80.

About 100 parts by weight of this material are mixed on a mill with about 30 parts by weight pulverized activated carbon, about 1 part by weight stearic acid and about 8 parts by weight puverized dicumyl peroxide (40%) and drawn out into a smooth sheet. This is vulcanized for 30 minutes at 150 C. The vulcanized material has the following physicals:

A' similar material is obtained=by using 3 parts by weight of ditertiary-butyl peroxideinstead of the dicumyl peroxide.

n ia ple' 4 In the same manner as described in Example 13, a thermoplastic material is produced from about 1,000

parts by weight of an adipic acid-propylene glycol polyester (hydroxyl number 56), about 15 parts by weight Tensile strength kg./cm. 224

Breaking elongation percent 740 Shore hardness 59 Rebound elasticity percent 36 Ring structure kg. abs./4 mm 17 Permanent elongation after 1 minute percent 15 Example 15 In the same manner as outlined under EXample 13, a

thermoplastic material is produced from about 1,000 parts by weight of an adipic acid-ethylene glycol-propylene glycol polyester (hydroxyl No. 56; glycol ratio 1:1) about 15 parts by weight butanediol, about 5 parts by weight butenediol and about 187 parts by weight 4,4- diphenyl methane-diisocyanate. The product has a Dcfo hardness of 1550/ 80 and a Defo elasticity of 30/ 80.

After mixing about 100 parts by weight of this material with about 25 parts by weight of pulverized activated carbon, about 1 part by weight of stearic acid and about 4 parts by weight of pulverized dicumyl peroxide (40%) and wlcanizing the mass under the conditions of Example 13, a vulcanized product is obtained with the following mechanical properties:

Tensile strength kg./cm. 235 Breaking elongation percent 665 Shore hardness 60 Rebound elasticity percent 39 Ring structure "kg. abs/4 mm 15 Permanent elongation after 1 minute percent 12 If about 30 parts by weight of silicic acid aerogel is used instead of the activated carbon, a material with similar properties is obtained.

Example 16 In the same manner as outlined under Example 13, a thermoplastic material is produced from about 900 parts by weight adipic acid-ethylene glycol-propylene glycol polyester (hydroxyl No. 56: ethylene glycol-propylene glycol ratio 7:3), about 18 parts by weight butanediol, and about 160 parts byweight 4,4-diphenyl methane diisocyanate. The product has a Defo hardness of 1175/ and a Defo elasticity of 36/80.' After mixing about parts by weight of this material with about 30 parts by weight of pulverized activated carbon and about 8 parts by weight pulverized dicumyl peroxide (40%) and vulcanizing the mass under the conditions of Example 13, a vulcanized product is obtained with the following mechanical properties:

Tensile Strength Breaking elongation 490 Shore hardnessuu 64 Rebound elasticity 43 Ring structure 8 Permanent elongation after 1 minute 8 Example 17 In the same manner as outlined under Example 13, a thermoplastic material is produced from about 1,000 parts by weight of adipic acid-ethylene glycol-polyester (hydroxy No. 56) about 20 parts by weight butanediol-1,3, and about 125 parts by weight tolylenediisocyanate. The product has a Defo hardness of 2550/ 80 and a Defo elasticity of 38/ 80. After mixing about 100 parts by weight of this material with about 30 parts by weight of pulverized activated carbon, about 1 part by weight stearic acid and about 8 parts by weight pulverized dicumyl peroxide and vulcanizing the mass under the conditions of Example 13, a vulcanized product is obtained with the following mechanical properties:

Tensile strength 180 Breaking elongation 345 Shore hardness 64 Rebound elasticity 41 Ring structure aa 11 Permanent elongation after 1 minute 16 Example 18 In the same manner as outlined under Example 13, a thermoplastic material is produced from about 1,000 parts by weight of an adipic acid-ethylene glycol polyester (hydroxyl No. 56), about 20 parts by weight of butanediol and about 191 parts by weight of 4,4-dicyclohexylmethane-diisocyanate. The product has a Defo hardness of 2450/ 80 and a Defo elasticity of 53/ 80". After mixing about 100 parts by weight of this material with about 35 parts by weight of pulverized activated carbon and about 8 parts by weight of pulverized dicumyl peroxide (40% and vulcanizing the mass under the conditions of Example 13, a vulcanized product is obtained with the following mechanical properties:

Tensile strength 182 Breaking elongation 345 Permanent elongation after 1 minute 7 A similar material is obtained by using about 2 parts by weight of tertiary butylhydroperoxide instead of the dicumyl peroxide.

Example 19 About 500 parts by weight of polybutylene glycol (hydroxyl No. 43) are dehydrated for one-half hour at 130 C. under vacuum in an agitated vessel. To this about 74 parts by weight of toluylene diisocyanate are added. The mass is allowed to react for 15 minutes, after which about 50 parts by weight of 4,4-dihydroxydicyclohexyl-dimethyl methane are added. Agitation is continued for another 3 minutes and then the mass is poured into trays. After heating in a drying oven for 12 hours at 100 C. a thermoplastic material is obtained with a Defo hardness of 2000/ 80, and a Defo elasticity of 36/ 80.

After mixing about 100 parts of this material with about 30 parts by Weight of pulverized activated carbon, about 1 part by weight of stearic acid and about 8 parts by weight of dicumyl peroxide (40%) and vulcanizing the mass under the conditions of Example 13, a vulcanized product is obtained with the following mechanical properties:

Example 20 About 1,000 parts by weight adipic acid-ethylene glycol polyester having an hydroxyl number of about 6 is mixed with about 50 quarts quinitol after the polyester has been dehydrated by heating to a temperature of about 130 C. About 162 parts, 2,4 toluylene diisocyanate are added and after chemical reaction the resulting product has a Defohardness of about 2,850 at and a Defo elasticity of 46 at 80.

About parts of the product is mixed with about 30 parts pulverized activated carbon, about 1 part stearic acid and about 8 parts dicumyl peroxide. The mixtures processed on a rubber mill for about 30 minutes at about 150 C. The resulting product has the following properties:

Tensile strength 129 Elongation at break 345 Shore hardness 64 Elasticity 31 Ring structure 9 Permanent elongation after 1 minute 12 Example 2] About 1,000 parts by weight adipic acid-propylene glycol polyester having an hydroxyl number of about 56 is mixed with about 50 parts hydroquinone-B-diethyl ether after the polyester has been dehydrated by heating to a temperature of about 130 C. About 202 parts, 4,4'-diphenylmethanediisocyanate are added and after chemical reaction the resulting product has a Defo-hardness of about 2,850 at 80 and a Defo elasticity of 46 at 80.

About 100 parts of the above material is mixed with about 30 parts activated carbon, pulverized, about 1 part stearic acid and about 8 parts dicumyl peroxide, pulverized (40%). The mixtures processed on a rubber mill for about 30 minutes at about 150 C. The resulting product has the following mechanical properties:

Tensile strength Breaking elongation 574 Shore hardness 70 Elasticity 36 Ring structure 22 Permanent elongation after 1 minute 19 Example 22 About 1,000 parts by weight adipic acid-ethylene glycol-polyester having an hydroxyl number of about 56 is mixed with about 15 parts butanediol and 5 parts butenediol after the polyester has been dehydrated by heating to a temperature of about 130 C. About 125 parts 2,4 toluylene diisocyanate are added and after chemical reaction the resulting product has a Defo hardness of about 700 at 80 and a Defo elasticity of 24 at 80.

About 100 parts of the above mixture is mixed with about 30 parts pulverized activated carbon, about 1 part stearic acid and about 8 parts pulverized dicumyl peroxide. The mixtures processed on a rubber mill for about 30 minutes at about C. The resulting product has the following mechanical properties:

Tensile strength 330 Breaking elongation 390 Shore hardness 79 Elasticity 41 Permanent elongation after 1 minute 2 Example 23 About 1000 parts by weight adipic acid ethylene glycol propylene glycol polyester having an hydroxyl number of about 59 and a glycol ratio of 7:3 is mixed with about 15 parts butanediol and about 5 parts butenediol after the polyester has been dehydrated by heating to a temperature of about 130 C. About 129 parts 2,4-toluylene diisocyanate are added and after chemical reaction the resulting product has a Defo hardness of about 5000 at 50 and a Defo elasticity of 50 at 50.

About 100 parts of the above mixture is mixed with about 25 parts pulverized activated carbon, about 1 part stearic acid and about 8 parts pulverized dicumyl perox- 11 ide (40%). The mixtures processedon a rubber mill for about 30 minutes at about 150 .C. The resulting product has the followingproperties:

Tensile strength 305 Elongation at break 435 Shore hardness 60 Elasticity. I 44 Permanent elongation after 1 minute 3 derstood that variations can be made therein by those skilled in the art without departing from the spirit of the invention and the scope of the claims.

What is claimed is:

1. A method for making a rubber-like polyurethane which comprises reacting an organic compound containing active hydrogen containing groups, a molecular weight of at least 1000, an hyd-roxyl number of less than 112 and selected from the group consisting of hydroxyl terminated 12 unsaturation other than aromatic, milling the resulting millable gum with from about 1 to about 10 percent by Weight of an organic peroxide as the sole curing agent, pressing said gum into a mold having the desired con- .figuration and curing-it at a temperature of from about C. to about C.

2. The process of claim 1 wherein said peroxide is dicumyl peroxide.

3. The process of claim 1 wherein said organic compound having hydrogen atoms is a polyester prepared by esterification of a dicarboxylic acid and a glycol.

4. The process of claim 1 wherein the organic compound containing hydrogen atoms is a polyalkylene ether glycol.

References Cited in the file of this patent I UNITED STATESPATENTS 2,431,921

Cook et a1., Dec. 2, 1947 2,621,166 Schmidt et a1. Dec. 9, 1952 2,625,531 Seeger Jan. 13, 1953 2,625,532 Seeger Jan. 13, 1953 2,734,045 Nelson Feb. 7, 1956 2,806,835 Nischk et al. Sept. 17, 1957 2,906,738 Goldberg Sept. 29, 1959 FOREIGN PATENTS 748,697 Great Britain May 9, 1956 776,979 Great Britain June 12, 1957 863,403 Germany Jan. 10, 1953 1,000,998 7 Germany Ian. 17, 1957 

1. METHOD FOR MAKING A RUBBER-LIKE POLYURETHANE WHICH COMPRISES REACTING AN ORGANIC COMPOUND CONTAINING ACTIVE HYDROGEN CONTAINING GROUPS, A MOLECULAR WEIGHT OF AT LEAST 1000, AN HYDROXYL NUMBER OF LESS THAN 112 AND SELECTED FROM THE GROUP CONSISTING OF HYDROXYL TERMINATED POLYESTERS OF POLYHYDRIC ALCOHOLS AND POLYCARBOXYLIC ACIDS AND POLYHYDRIC POLYALKYLENE ETHERS WITH AN EXCESS OF AN ORGANIC POLYISOCYANATE AND A QUANTITY OF A GLYCOL HAVING A MOLECULAR WEIGHT SUBSTANTIALLY LESS THAN 1000 AT LEAST SUFFICIENT TO REACT WITH ALL OF THE -NCO GROUPS PRESENT, SAID COMPOUNDS BEING FREE FROM ANY CARBON TO CARBON UNSATURATION OTHER THAN AROMATIC, MILLING THE RESULTING MILLABLE GUM WITH FROM ABOUT 1 TO ABOUT 10 PERCENT BY WEIGHT OF AN ORGANIC PEROXIDE AS THE SOLE CURING AGENT, PRESSING SAID GUM INTO A MOLD HAVING THE DESIRED CONFIGURATION AND CURING IT AT A TEMPERATURE OF FROM ABOUT 120*C. TO ABOUT 160*C. 